In secondary recovery wells, i.e., those employing some form of a pump, a sucker rod typically extends between the downhole pump and the "rocking horse" actuator on the surface. The sucker rod is vertically reciprocated in the tubing string by the rocking horse to actuate the pump. In order to center the rod in the tubing string, twist-on guides are snapped onto the rod. These rod guides are typically made of rubber nylon and perform a secondary function of transferring the wear to the bushing-like rod guide rather than permitting the rod itself to wear as a result of the friction between the stationary tubing and moving rod. In addition, the softer, self-lubricating rod guides reduce abrasion of the tubing string itself. The twist-on rod guide comprises a generally cylindrical bushing with tapered top and bottom ends having a front and back and a first axially extending aperture or throughbore. The first axially extending aperture intersects front of the guide and defines a first axially extending slot. Further, the first aperture intersects the back of the guide and defines a second axial slot. A second diagonally extending aperture interconnects said first and second slots.
Under current practice, the rod guides, which of necessity fit snugly on the sucker rod in order to prevent riding up the rod, are hammered into position on the sucker rod and then, when replacement is necessary, hammered off the rod. In addition to the potential damage to the rod guide involved with this method, there is potential damage to the rod itself as a result of an errant hammer blow or one that is more forceful than necessary. A damaged, i.e., dented or bent, sucker rod section must then be changed out with associated expense and lost production time.
The present invention is directed to a simple, yet effective, tool and method for installing twist-on guides onto, and removing worn guides off from, sucker rods. A first C-shaped plate member has first and second parallel arms with rod guide engaging surfaces and lies substantially in a first plane. A pry bar is affixed to one edge of the second arm. A projection of the pry bar into the plane of the plate member forms a right angle with the edge of the arm. The pry bar lies in a second plane that forms an angle, preferably about 20.degree., with the plane of the plate member. A handle forms an extension of the pry bar.
In use, the applicator tool of the present invention is positioned with the first and second arms of the plate member surrounding the rod guide and the sucker rod, the diagonally extending slot of the guide receiving said rod. The engaging surfaces are simultaneously brought into contact with a first portion of a back side of the rod guide opposite the first axial slot that is above the diagonal slot and a second portion of the back side opposite a second axial slot that is below the diagonal slot. By applying a downward force to the handle and/or pry bar, the centerline of the axial opening or aperture in the rod guide is brought into alignment with the centerline of and snapped onto the sucker rod. To remove a worn guide, the tool is reversed and the engaging surfaces of the tool brought into contact with a first pair of surfaces strattling the first axial slot and a second pair of surfaces strattling the second axial slot. By exerting upward force on the pry bar or handle, the guide can be snapped off the sucker rod and replaced with a new one as detailed above.
Various other features, advantages and characteristics will become apparent after a reading of the following detailed description.